Boa Sub C - Offshore Support Vessel

The Boa Sub C and Boa Deep C are two offshore support vessels designed to meet Chevron's deepwater offshore developments in the Gulf of Mexico. The Boa Sub C will be used for the offshore installation activities of Chevron's Blind Faith platform.

BOA SUB C

The Boa Sub C has an overall length of 120m, a moulded breadth of 27m and a draught of 8.8m. The depth to the first deck is 11.6m and 7.8m to the second. Gross tonnage is 12,400t and deadweight is 9,000t. The vessel has a helideck designed for a Super Puma/S61 helicopter.

The accommodation facilities can cater for 90 persons in 90 cabins, with ten cabins also equipped with Pullman beds.

The Boa Sub C has a fuel oil capacity of around 2,800m³ and can carry 3,700m³ water ballast/drill water. It can also carry 1,300m³ of fresh water.

The vessel can also carry tanks of lube oil (200m³), hydraulic oil (65m³) oily water (45m³), sewage (140m³), grey water (140m³), sludge ( 87m³) waste oil (75m³), drain ( 27mf³) and bilge (30m³).

BOA DEEP C

The Boa Deep C has two workclass remotely operated underwater vehicle (ROV) hangars on its port and starboard. It uses two Oceaneering Millenium-designed ROVs rated at 3,000m water depth. The ROVs can be deployed in a typical wave height of 4.5m.

The ship has 1,150m² of free deck space. In order to carry out installation work, the deck is reinforced for a specific load of 15t per square meter. The vessel is also fitted with a 7.2m by 7.2m moon pool.

Power is provided by two 2,420kW generator sets, two 1,820kW sets and a 910kW genset. There is also a pair of 4,800kW shaft generators, giving a total capacity of 18,992kW.

The vessel's main propulsion is based on two 9,000kW engines and a 1,200kW azimuthing propeller, giving a total output of 19,200kW. In order to manoeuvre, there is a pair of fore and aft 1,425kW tunnel thrusters.

The Boa Deep C's total thrust capacity is 6,900kW, allowing a bollard pull of over 260t, a maximum speed of 15kt and an economy speed of 12.5kt. The vessel is equipped with anti-heel and roll damping tanks.

The ship has an active heave compensated crane with a 250t lifting capacity at 15m and a working depth of 2,000m. A 500t anchor handling drum (with an inner diameter of 3,500mm and a 5,700mm external diameter) has a capacity for 8,100m of 90mm diameter wire.